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| 1 | Phylogenetic alpha and beta diversity in tropical tree assemblages along regionalscale environmental gradients in northwest South America显示文摘Aims Environmental gradients are drivers of species diversity;however,we know relatively little about the evolutionary processes underlying these relationships.A potentially powerful approach to studying diversity gradients is to quantify the phylogenetic structure within and between assemblages arrayed along broad spatial and environmental gradients.Here,we evaluate the phylogenetic structure of plant assemblages along an environmental gradient with the expectation that the habitat specialization of entire lineages is an important evolutionary pattern influencing the structure of tree communities along environmental gradients.Methods We evaluated the effect of several environmental variables on the phylogenetic structure of plant assemblages in 145 plots distributed in northwestern South America that cover a broad environmental gradient.The phylogenetic alpha diversity was quantified for each plot and the phylogenetic beta diversity between each pair of plots was also quantified.Both the alpha and beta diversity measures were then related to spatial and environmental gradients in the study system.Important Findings We found that gradients in temperature and potential evapotranspiration have a strong relationship with the phylogenetic alpha diversity in our study system,with phylogenetic overdispersion in low temperatures and phylogenetic clustering at higher temperatures.Further,the phylogenetic beta diversity between two plots increases with an increasing difference in temperature,whereas annual precipitation was not a significant predictor of community phylogenetic turnover.We also found that the phylogenetic structure of the plots in our study system was related to the degree of seasonal flooding and seasonality in precipitation.In particular,more stressful environments such as dry forests and flooded forests showed phylogenetic clustering.Finally,in contrast with previous studies,we find that phylogenetic beta diversity was not strongly related to the spatial distance separating two forest plots,which may be the result of the importance of the three independent mountain ranges in our study system,which generate a high degree of environmental variation over very short distances.In conclusion,we found that environmental gradients are important drivers of both phylogenetic alpha and phylogenetic beta diversities in these forests over spatial distance. | Sebastián González-Caro María Natalia Umaña Esteban Álvarez Pablo R.Stevenson Nathan G.Swenson | 2014 | Journal of Plant Ecology2014，7，2： | 17 |
| 2 | Prognostic factors for recurrence of gastrointestinal bleeding due to Dieulafoy's lesion显示文摘AIM:To analyze the effectiveness of the endoscopic therapy and to identify prognostic factors for recurrent bleeding.METHODS:Retrospective study of patients with gastrointestinal bleeding secondary to Dieulafoy's lesion(DL) from 2005 to 2011.We analyzed the demographic characteristics of the patients,risk factors for gastrointestinal bleeding,endoscopic findings,characteristics of the endoscopic treatment,and the recurrence of bleeding.We included cases in which endoscopy described a lesion compatible with Dieulafoy.We excluded patients who had potentially bleeding lesions such as angiodysplasia in other areas or had undergone other gastrointestinal endoscopic procedures.RESULTS:Twenty-nine patients with DL were identified.Most of them were men with an average age of 71.5 years.Fifty-five percent of the patients received antiaggregatory or anticoagulant therapy.The most common location for DL was the stomach(51.7%).The main type of bleeding was oozing in 65.5% of cases.In 27.6% of cases,there was arterial(spurting) bleeding,and 6.9% of the patients presented with an adherent clot.A single endoscopic treatment was applied to nine patients(31%);eight of them with adrenaline and one with argon,while 69% of the patients received combined treatment.Six patients(20.7%) presented with recurrent bleeding at a median of 4 d after endoscopy(interquartile range = 97.75).Within these six patients,the new endoscopic treatment obtained a therapeutic success of 100%.The presence of arterial bleeding at endoscopy was associated with a higher recurrence rate for bleeding(50% vs 33.3% for other type of bleeding) [P = 0.024,odds ratio(OR) = 8.5,95% CI = 1.13-63.87].The use of combined endoscopic treatment prevented the recurrence of bleeding(10% vs 44.4% of single treatment)(P = 0.034,OR = 0.14,95% CI = 0.19-0.99).CONCLUSION:Endoscopic treatment of DL is safe and effective.Adrenaline monotherapy and arterial(spurting) bleeding are associated with a high rate of bleeding recurrence. | Yuliana Jamanca-Poma Antonio Velasco-Guardado Concepción Piero-Pérez Renzo Calderón-Begazo Josue Umaa-Mejía Fernando Geijo-Martínez Antonio Rodríguez-Pérez | 2012 | World Journal of Gastroenterology2012，18，40： | 11 |
| 3 | Radiation protection by the ocimum flavonoids orientin and vicenin:mechanisms of action 显示文摘 | Uma Devi P Ganasoundari A Vrinda B | 2000 | Radiat Res2000，154，4： | 1 |
| 4 | Copper(Ii) complexes of N4 tetradentate ligands with flexible alkyl spacers: Crystal structure, DNA binding and cleavage studies 显示文摘 | UMA V CASTINEIRAS A NAIR B U | 2007 | Polyhedron2007，26，30： | 1 |
| 5 | Immunoglobulin G,A,and M responses in serum and circulating immune complexes e-licited by the 16-kilodalton antigen of Mycobacterium tuberculosis显示文摘 | Raja A Uma Devi KR Ramalingam B | 2002 | Clin Diagn Lab Immunol2002，9，2： | 1 |
| 6 | Protection against radiation-induced chromosome damage in mouse bone marrow by Ocimum sanctum显示文摘 | GANASOUNDARI A UMA DEVI P RAO M N A | 1997 | Mutation Research1997，373，： | 1 |
| 7 | Enhanced control of integrating cascade processes with time delays using modified Smith predictor 显示文摘 | Uma S Chidarnbaram M Rao Seshagiri A Yoo C K | 2010 | Chemical Engineering Science2010，65，： | 1 |
| 8 | Studies on the Development of a Conductive Surface on DielectricAnodic Film显示文摘 | Uma Rani R Sharma A K | 2004 | Galvanotechnik2004，95，3： | 1 |
| 9 | The variable precision rough set inductive logic programming model and web usage graphs显示文摘 | MAHESWARI A UMA V SIROMONEY A | 2001 | New Frontiers in Artificial Intelligence-Joint JSAI 2001 Workshop Post-Proceedings2001，2253，： | 1 |
| 10 | Immunoglobulin G, A, and M respenses in serum and circulating immune complexes elicited by the 16-kilodalton antigen of Mycobacterium tuberculosis 显示文摘 | Raja A Uma Devi KR Ramalingam B Brennan PJ | 2002 | Clin Diagn Lab Immunol2002，9，2： | 1 |
| 11 | Inhibition of DNA repair as a mechanism of enchanced radiorespones of head and neck carcinoma cells by a selective cyclooxygenase-2 inhibitor,celecoxib 显示文摘 | Uma R Hisanori A Klaus D | 2006 | Int J Radial Oncol Biol Phys2006，63，： | 1 |
| 12 | Altered cardiac tissue and plasma kininogen levels in hypertensive and diabetic rats 显示文摘 | SHARMA J N UMA K YUSOF A P | 1999 | Immunopharmacology1999，34，： | 1 |
| 13 | Enhanced control of integrating cascade processes with time delays using modified Smith predictor显示文摘 | Uma S Chidambaram M Rao Seshagiri A Yoo C k | 2010 | Chemical Engineering Science2010，65，： | 1 |
| 14 | Me- tastasis of squamous cell carcinoma of the oral tongue is associated with downregulation of epidermal fatty acid binding protein (E-FABP)显示文摘 | UMA R S NARESH K N DfCRUZ A K | 2007 | Oral Oncol2007，43，： | 1 |
| 15 | Inhibition of DNA repair as a mechanism of enchanced radiorespones of head and neck carcinoma cells by a selective cyclooxygenase-2 inhibitor,celecoxib显示文摘 | Uma R Hisanori A Klaus D | 2006 | Int J Radiat Oncol Biol Phys2006，63，2： | 1 |
| 16 | Temperature-dependent thermal conductivity of undoped polycrystalline silicon layers显示文摘 | Uma S McConnell A D Asheghi M | | 0，，02： | 1 |
| 17 | Protection a- gainst radiation-induced chromosome damage in mouse bone marrow by Oclrnum sancyum显示文摘 | Canasoundari A Uma Devi P Rao M N A | 1997 | Mutation Research1997，373，： | 1 |
| 18 | Specific and early detection of IgG,IgA and IgM antibodies to Mycobacterium tuberculosis 38kDa antigen in pulmonary tuberculosis显示文摘 | Uma Devi KR Ramalingam B Brennan PJ Narayanan PR Raja A | 2001 | Tuberculosis (Edinb)2001，81，3： | 1 |
| 19 | Persistently high venous-to-arterial carbon dioxide differences during early resuscitation are associated with poor outcomes in septic shock显示文摘 | Ospina-Tascón GA Bautista-Rincón DF Uma(n)a M | 2013 | Crit Care2013，17，： | 1 |
| 20 | Radiation protection by the oeimum flavonoids orientin and vicenin mechanisms of action 显示文摘 | Uma Devi P Ganasoundari A Vfinda B | 2000 | Radiat Res2000，154，4： | 1 |
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